Nah, I still think Popplio would have gotten shafted if it was given to Ash. I'll give you that it would probably benefit from being able to interact with more Pokemon on a regular basis, but that's all it would really do. On the flip side, it would most likely never evolve because the writers are practically allergic to giving feminine Pokemon to male characters for the most part nowadays, and it would remain one of the weaker members of his team. Especially given how aquatic of a Pokemon Popplio is (I've noted multiple times that I feel like that is what's hindering Lana and Popplio's development; they very rarely do anything outside of those aquatic settings). It would probably be the Oshawott of the generation, not Rowlet, because it would need to have something to make up for it not evolving. Maybe you think that would make it more memorable; I think it would have just turned it into another Scrappy, just like the others. While I wish Popplio was treated better, I'd rather it be unremarkable than be hated. And while I know you don't particularly care about evolution, a lot of people do.
Also, I recall something you said earlier, that Popplio itself was pretty much just a basic, generic sea lion, while Brionne moreso embodies the "performer" aspect of the line. Well, Popplio could potentially be one of those Pokemon that evolution could benefit personality-wise from evolution (I feel the same about Tsareena btw as Steenee itself is pretty generic too IMO).